When plotting multiple pages (like "all.dem" in the demo directory) using the
postscript of enhanced postscript terminal, a PostScript error occurs when rendering the page generated by "enhanced_utf8.dem", probably because the generated
pages are not independent of each other.
The said page renders OK if generated as a single PS file.
Mac OS X 5.8.3, gnuplot 4.6.3, compiled from the sources.